Harvester-platform adjustment



`UNiTnD 'STATES- PATENT OFFICE.

MAURICE KANE, OE CHICAGO, ILLINOIS, ASSIGNOR TO Tl-IE WARDER, BUSH- NELL du GLESSNER COMPANY, OF SAME PLACE, AND SPRINGFIELD, OHIO.

HARVESTER-PLATFORM ADJUSTMENT.

SPECIFICATION forming part of Letters Patent No. 499,837', dated June 20, 1893.

Application filed December 31, 1892. Serial No. 456,940. (No model.)

T0 aZZ whom it may concern:

Be it known that I, MAURICE KANE, a citi Zen of the United States, residing at Chicago, county of Cook, and State of Illinois, haveinvented certain new and useful Improvements in Harvester-Platform Adjustments, which are fully set forth in the following specification, reference being had to the accompanying drawings, forming a part thereof.

The purpose of this invention is to provide improved devices for adjusting` the platform of a harvesting machine, and consists of a novel expedient for maintaining the driving chain suitably taut under all conditions of adjustment of the platform, and in certain details described and set forth in the claims. In the drawings,-Figure l is a side elevation of a portionof the fr'ame and of the tliive\vheel and platform adjusting devices. Fig. 2 is a det-ail section at the plane indicated by the line 2-2 on Fig. 1.

A is the drive-wheel; B the platform-frame.

A is the main driving sprocket-wheel or master-wheel on the drive-wheel.

B is one of the raising and lowering segments rigid with the main frame.

` The construction herein represented embodies the mode of ldriving which is in general familiar, wherein power is transmitted from the master-wheel A by drive-chain, whose course is represented by the broken line C extending about said master-wheel, and the main driving sprocket pinion D on the main driving shaft CZ journaled on the main frame and carrying the beveled gearwheel: E, which meshes with the beveled pinion F on the fore-and-aft shaft f, which carries at the forward end the sickle crank wheel F and at the rear end the sprocket-wheel F2, from which power may be communicated to other mechanism on the harvester. The construction shown is also familiar in that the raising and lowering` of the frame are effected by means of pinions, of which one is shown at H,on the drive-wheel axle h, meshing respectively with the racks of the raising and lowering segments, the axle having rigid with it also the worin-wheel J, which is rotated by means of the worm K on the shaft 7e, said worm being held in mesh with the wormwheel by journaling in bearings L L in the two-part case L, which incloses and protects the worm-wheel J; the shaft lo extending to a convenient point on the frame where it may be rotated by the crank 7e to operate the l worm and rotate the worm-wheel, and thereby the axle and the pinions I-I thereon to cause them to travel in their respective segments. It has been customary in constructions of this general character in harvesters to construct the raising and lowering segments conformed to an arc of a circle about the axis of the shaft which is driven by the chain on the master-wheel; that is to say, referring to the drawings, in the arc of a circle about the shaft d. The obvious reason for this construction is that the center of the master-wheel is thereby adj usted relatively in an arc about the center of the shaft to which it communicates motion and therefore preserves its distance -from that shaft unchanged through all the adjustments, and by this means no change in the length of drive-chain necessary to encompass both wheels, is made necessary by the change of adjustment. This construction would be practically correct, asit seems to be theoretically, but for the fact that it is always necessary to allow for slack in the chain because by reason of wear there soon exists slack even though none is provided for in the first construction, and it will be necessary to provide a tightener or take-up pulley to compensate for this slack; and it is evident that this take-up pulley or tightener must move with the master-wheel and axle in its adjustment (or, more correctly, must stay with those parts as.. the frame is adjusted), or else its own change of position relatively to the chain on which it is to operate will deprive it of capacity for performing its function of taking up the slack uniformly at all adjustments.

Whenever the construction above referred to,v-the segments being curved in arcs about the axis'of the main driving shaft CZ,-is eniployed, some expedient must be resorted to to keep the tightener practically unchanged in its relation to the axle throughout these adjustments, and since the tightener pulley is most naturally and easily mounted in some manner upon the frame, and is not easily Amounted in connection with the axle, these devices usually take the forni of expediente IOO for giving the tightener wheel a movement relatively to the frame sufficient to compensate for its movement with the'frame in the adjustment of the elevation of the latter. As distinguished from this class of devices and expedients, my invention consists in curving the. segments eccentrically with respect to the main driven shaft d so that the adjustment of the main frame and segments with respect to the dri ve-wheel axle tends to vary the length of chain required to encompass the master-wheel and main sprocket pinion, and in providing a tightener or take-up pulley which is rigidly fixed on the main frame in such position that the change of position of the master-wheel with respect thereto in the direction which tends to slacken the chain, causes the chain to be defiectedover the tighten er pulley sufficiently to compensate for such slackening.

M is the tightener pulley or take-up journaled in a suitable hanger M bolted fast to the main frame with suitably slotted connection to permit a slight variation to compensate for wear of the chain from time to time, but rigid with respect to the main frame except as it may be adjusted in this respect. The tightener will preferably be located in contact with the deck or idle lside of the chain; that is, the side which runs from and not to the driving master-wheel, and vin the arrangement of parts shown in the drawings, this is the lower side of the chain. The direction of y adjustment of the main axle in the segment which carries the axle toward the driving vside will be that which will cause the .chain to be tightened or taken up by folding over the tightener pulley M; it is therefore this direction of adjustment that should afford the necessary compensation by bringing the axle nearer to the axis of the main driven shaft d. The center of curvature of the segment will therefore be so located with respect to the axis of the shaft d that the arc of the segment shall fall within an arc about the axis of the shaft d struck from the highest point of the axle downward. Such arc is represented by the dotted line h and the distance inward from the lower end of that dotted are to the dotted arc h2, which is the path of the axis of the axle as it follows the segment, indicates the amount of slack the chain would derive from the adjustment of the axle t A i mechanic will readily ascertain bya little experiment at what point to locate the tightenerI M so that this amount of slack will be com through the entire range of the segment.

pensated by the deflection of the lower ply of the chain as the latter is necessarily foldedl over the tightener by such change of position of the axle in the segment, and the tightener will thereby be made to compensate perfectly for the eccentricity of the segment. Or,-to describe the result from a point of view corresponding-to the order of conception,--the eccentricity of the segment will thereby compensate perfectly for thevslackening or tightening of the chain caused by the raising and lowering of the frame to which the tightener bearings are fixed. All necessity for ,complicated connections between the tightener wheel bearings and the axle and the main frame to compensate its movement `with the frame by a movementwith respect to the frame, are avoided. y

An especial advantage is derived from the position of the segment which results from locating it eccentrically with respect to the main driven shaft d, as shown in the drawings; that is to say, with a forward inclination with respect to the main frame or plane of the principal right-and-left and fore-andaft shafts, as, for example, shaftsfand d in the drawings. This advan tage consistsin the tend-V ency which this inclination has to preserve the proper balance of themachine at all elevations. This will bel understood when it is borne in mind that aharvester platform and main frame are adjusted low under two situations or conditions, vim: when cutting lodged grain, and when cutting short grain. If the grain is lodged the machine will be tilted down in front as well as adjusted low, and thereby the center of gravity of the machine will be thrown forward, and but for compensating expedients would tend to overbalance it forward if it were properly balan'ced at a horizontal position.

If the position is adj usted low for short grain the binder will be set fors Ward to a corresponding degree, and this will cause the center of gravity of the machine to be located-farther forward than under ordinary conditions; and 4but for compensating expedients would tend to overbalance the machine forward. The inclination ofthe segments causing the entire machine to be moved rearward with respect to the axle as it is lowered on the axle compensates for the forward shifting of the center ofv gravity which may be due either to the tilting of the machine forward for lodged grain, or to the IOO IIO

adjustment of the binder forward for short grain, and the result is that the machine may be kept almost accurately balanced at all elevations by this expedient, and I design to employ this expedient of setting the segments with a forward inclination, for this purpose, without regard to the eccentricity vof the segmentswith respect to the main driven" 'shaft for the other purpose above indicated.

In connection with the device as above described I have employed an expedient for preventing thecramping of the shaft 7c and making it eas-y to adjust the machine, which consists in providing a guide and stop connection between the two-part case L and the segment. It will be understood that the tendworm-Wheel with the Worm K and the journaling of the worm in the case L and the checking of the rotary movement of the case, or of the worm, about the axle by some means. It is common to rely upon the shaft 7e, which is journaled on the frame always at a considerable distance from the worm, to prevent this rotation of the case and thereby to cause the segment to remain elevated on the pinion except as the rotation of the Worm-wheelby the Worm permits it to change its position. This puts a strain upon the shaft K tending to bend it, making it difiicult to rotate it in its bearings. I relieve the Worm shaft of this strainby checking the rotation of the caseL by direct engagement of the case with the segment. Such engagement is made by the flange b projecting inward from the segment in an arc coinciding with the inner margin of the opening in the segment and extending beyond the opening to the upper end of the segment, and providing a recess Z2 on the proximate face of the case L into Which the flange b may take and so may check the rotation of the case While permitting freely the vertical adj ustment'which will cause the an ge to slide in the recess as the machine is raised and lowered. This recess Z2 is most conveniently produced by throwing out two small lugs F0 X20 from the face of the case which constiiute a little fork striding the flange b.

N is a lug or bracket which projects up from the bearing of the shaft d on the main frame and affords a bearing at n for the shaft 7c. Preferably, but not of necessity, this bearing is located at the center of curvature of the segment, and I have so illustrated it, for the obvious reason that the adjustment of the main frame and Segments about the axlecarrying the lug or bracket N will not displace the bearing n when it is so located, and the bearing need therefore only be made sufficiently free to permit the swinging of the rod vor shaft K in it through the angle of adjustment, Whereas if it were located aside from that center line it would be necessary not only to make it exceedingly free but it would also be necessary to make the bearing of the Worm or its connection with the shaft quite free in order to avoid binding as the machine is adjusted.

I claimr l. In a harvester, the main frame, the drive- Wheel and the raising and lowering segments rigid With the main frame for adjusting it With respect to the drive-Wheel axle, the main driven shaft journaled on the frame eccentrically with respect to the segments, and the tightener or take-up pulley mounted on the frame, combined and operating substantially as set forth.

` 2. In combination with the main frameand the raising and lowering segments rigid therewith, the drive-wheel axle and the pinions thereon which engage the segments, and the Worm-Wheel rigid with the axle and the Worm which engages it, the Worm-Wheel case centered about the' axle and affording bearings for the worm shaft, the main driven shaft 'journaled on the main frame eccentrically with respect to the segments, .a bearing for the Worm shaft xed on the main frame at the center of curvature of the segments, said Worm shaft extending past the main driven shaft, and provided with means for rotating it beyond the latter shaft, substantially as set forth.

In testimony whereof I have hereunto set my hand, in the presence of two Witnesses, at Chicago, Illinois, this 23d day of December, 1892.

MAURICE KANE.

Witnesses:

CHAs. S. BURTON,- JEAN ELLIOTT. 

